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                <ol class="chapter"><li class="chapter-item expanded "><a href="../../preface.html"><strong aria-hidden="true">1.</strong> Preface</a></li><li class="chapter-item expanded "><a href="../../ch01/ch01.html"><strong aria-hidden="true">2.</strong> Chapter 1</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../ch01/1.1/1.1.html"><strong aria-hidden="true">2.1.</strong> Section 1.1</a></li><li class="chapter-item expanded "><a href="../../ch01/1.3/1.3.html"><strong aria-hidden="true">2.2.</strong> Section 1.3</a></li><li class="chapter-item expanded "><a href="../../ch01/1.6/1.6.html" class="active"><strong aria-hidden="true">2.3.</strong> Section 1.6</a></li></ol></li><li class="chapter-item expanded "><a href="../../ch02/ch02.html"><strong aria-hidden="true">3.</strong> Chapter 2</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../ch02/key-point/key-point.html"><strong aria-hidden="true">3.1.</strong> KeyPoints</a></li><li class="chapter-item expanded "><a href="../../ch02/2.2/2.2.html"><strong aria-hidden="true">3.2.</strong> Section 2.2</a></li><li class="chapter-item expanded "><a href="../../ch02/2.3/2.3.html"><strong aria-hidden="true">3.3.</strong> Section 2.3</a></li><li class="chapter-item expanded "><a href="../../ch02/2.4/2.4.html"><strong aria-hidden="true">3.4.</strong> Section 2.4</a></li><li class="chapter-item expanded "><a href="../../ch02/2.6/2.6.html"><strong aria-hidden="true">3.5.</strong> Section 2.6</a></li><li class="chapter-item expanded "><a href="../../ch02/2.8/2.8.html"><strong aria-hidden="true">3.6.</strong> Section 2.8</a></li></ol></li><li class="chapter-item expanded "><a href="../../ch03/ch03.html"><strong aria-hidden="true">4.</strong> Chapter 3</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../ch03/key-point/key-point.html"><strong aria-hidden="true">4.1.</strong> KeyPoints</a></li><li class="chapter-item expanded "><a href="../../ch03/3.1/3.1.html"><strong aria-hidden="true">4.2.</strong> Section 3.1</a></li><li class="chapter-item expanded "><a href="../../ch03/3.3/3.3.html"><strong aria-hidden="true">4.3.</strong> Section 3.3</a></li><li class="chapter-item expanded "><a href="../../ch03/3.4/3.4.html"><strong aria-hidden="true">4.4.</strong> Section 3.4</a></li><li class="chapter-item expanded "><a href="../../ch03/3.5/3.5.html"><strong aria-hidden="true">4.5.</strong> Section 3.5</a></li><li class="chapter-item expanded "><a href="../../ch03/3.6/3.6.html"><strong aria-hidden="true">4.6.</strong> Section 3.6</a></li><li class="chapter-item expanded "><a href="../../ch03/3.7/3.7.html"><strong aria-hidden="true">4.7.</strong> Section 3.7</a></li><li class="chapter-item expanded "><a href="../../ch03/3.8/3.8.html"><strong aria-hidden="true">4.8.</strong> Section 3.8</a></li><li class="chapter-item expanded "><a href="../../ch03/3.9/3.9.html"><strong aria-hidden="true">4.9.</strong> Section 3.9</a></li></ol></li><li class="chapter-item expanded "><a href="../../ch04/ch04.html"><strong aria-hidden="true">5.</strong> Chapter 4</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../ch04/key-point/key-point.html"><strong aria-hidden="true">5.1.</strong> KeyPoints</a></li><li class="chapter-item expanded "><a href="../../ch04/4.2/4.2.html"><strong aria-hidden="true">5.2.</strong> Section 4.2</a></li><li class="chapter-item expanded "><a href="../../ch04/4.3/4.3.html"><strong aria-hidden="true">5.3.</strong> Section 4.3</a></li><li class="chapter-item expanded "><a href="../../ch04/4.4/4.4.html"><strong aria-hidden="true">5.4.</strong> Section 4.4</a></li><li class="chapter-item expanded "><a href="../../ch04/4.5/4.5.html"><strong aria-hidden="true">5.5.</strong> Section 4.5</a></li><li class="chapter-item expanded "><a href="../../ch04/4.6/4.6.html"><strong aria-hidden="true">5.6.</strong> Section 4.6</a></li><li class="chapter-item expanded "><a href="../../ch04/4.7/4.7.html"><strong aria-hidden="true">5.7.</strong> Section 4.7</a></li></ol></li><li class="chapter-item expanded "><a href="../../ch05/ch05.html"><strong aria-hidden="true">6.</strong> Chapter 5</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../ch05/5.1/5.1.html"><strong aria-hidden="true">6.1.</strong> Section 5.1</a></li><li class="chapter-item expanded "><a href="../../ch05/5.2/5.2.html"><strong aria-hidden="true">6.2.</strong> Section 5.2</a></li><li class="chapter-item expanded "><a href="../../ch05/5.3/5.3.html"><strong aria-hidden="true">6.3.</strong> Section 5.3</a></li><li class="chapter-item expanded "><a href="../../ch05/5.4/5.4.html"><strong aria-hidden="true">6.4.</strong> Section 5.4</a></li><li class="chapter-item expanded "><a href="../../ch05/5.5/5.5.html"><strong aria-hidden="true">6.5.</strong> Section 5.5</a></li></ol></li><li class="chapter-item expanded "><a href="../../ch06/ch06.html"><strong aria-hidden="true">7.</strong> Chapter 6</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../ch06/6.1/6.1.html"><strong aria-hidden="true">7.1.</strong> Section 6.1</a></li><li class="chapter-item expanded "><a href="../../ch06/6.2/6.2.html"><strong aria-hidden="true">7.2.</strong> Section 6.2</a></li><li class="chapter-item expanded "><a href="../../ch06/6.3/6.3.html"><strong aria-hidden="true">7.3.</strong> Section 6.3</a></li><li class="chapter-item expanded "><a href="../../ch06/6.4/6.4.html"><strong aria-hidden="true">7.4.</strong> Section 6.4</a></li><li class="chapter-item expanded "><a href="../../ch06/6.5/6.5.html"><strong aria-hidden="true">7.5.</strong> Section 6.5</a></li><li class="chapter-item expanded "><a href="../../ch06/6.6/6.6.html"><strong aria-hidden="true">7.6.</strong> Section 6.6</a></li><li class="chapter-item expanded "><a href="../../ch06/6.7/6.7.html"><strong aria-hidden="true">7.7.</strong> Section 6.7</a></li></ol></li><li class="chapter-item expanded "><a href="../../ch07/ch07.html"><strong aria-hidden="true">8.</strong> Chapter 7</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../ch07/7.2/7.2.html"><strong aria-hidden="true">8.1.</strong> Section 7.2</a></li><li class="chapter-item expanded "><a href="../../ch07/7.3/7.3.html"><strong aria-hidden="true">8.2.</strong> Section 7.3</a></li><li class="chapter-item expanded "><a href="../../ch07/7.3/7.4.html"><strong aria-hidden="true">8.3.</strong> Section 7.4</a></li><li class="chapter-item expanded "><a href="../../ch07/7.5/7.5.html"><strong aria-hidden="true">8.4.</strong> Section 7.5</a></li><li class="chapter-item expanded "><a href="../../ch07/7.6/7.6.html"><strong aria-hidden="true">8.5.</strong> Section 7.6</a></li><li class="chapter-item expanded "><a href="../../ch07/7.7/7.7.html"><strong aria-hidden="true">8.6.</strong> Section 7.7</a></li></ol></li><li class="chapter-item expanded "><a href="../../ch08/ch08.html"><strong aria-hidden="true">9.</strong> Chapter 8</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../ch08/8.2/8.2.html"><strong aria-hidden="true">9.1.</strong> Section 8.2</a></li><li class="chapter-item expanded "><a href="../../ch08/8.3/8.3.html"><strong aria-hidden="true">9.2.</strong> Section 8.3</a></li><li class="chapter-item expanded "><a href="../../ch08/8.4/8.4.html"><strong aria-hidden="true">9.3.</strong> Section 8.4</a></li><li class="chapter-item expanded "><a href="../../ch08/8.5/8.5.html"><strong aria-hidden="true">9.4.</strong> Section 8.5</a></li></ol></li></ol>
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                        <h1 id="exercises-for-section-16"><a class="header" href="#exercises-for-section-16">Exercises for Section 1.6</a></h1>
<h3 id="161"><a class="header" href="#161">1.6.1</a></h3>
<p>For the block-structured C code below, indicate the values assigned to w, x, y, and z.</p>
<pre><code>int w, x, y, z;
int i = 4; int j = 5;
{
  int j = 7;
  i = 6;
  w = i + j;
}
x = i + j;
{
  int i = 8;
  y = i + j;
}
z = i + j;
</code></pre>
<h4 id="answer"><a class="header" href="#answer">Answer</a></h4>
<p>w = 13, x = 11, y = 13, z = 11.</p>
<h3 id="162"><a class="header" href="#162">1.6.2</a></h3>
<p>Repeat Exercise 1.6.1 for the code below.</p>
<pre><code>int w, x, y, z;
int i = 3; int j = 4;
{
  int i = 5;
  w = i + j;
}
x = i + j;
{
  int j = 6;
  i = 7;
  y = i + j;
}
z = i + j;
</code></pre>
<h4 id="answer-1"><a class="header" href="#answer-1">Answer</a></h4>
<p>w = 9, x = 7, y = 13, z = 11.</p>
<h3 id="163"><a class="header" href="#163">1.6.3</a></h3>
<p>For the block-structured code of Fig. 1.14, assuming the usual static scoping of
declarations, give the scope for each of the twelve declarations.</p>
<h4 id="answer-2"><a class="header" href="#answer-2">Answer</a></h4>
<pre><code>Block B1:
	declarations:  -&gt;   scope
		w				B1-B3-B4
		x				B1-B2-B4
		y				B1-B5
		z				B1-B2-B5
Block B2:
	declarations:  -&gt;   scope
		x				B2-B3
		z				B2
Block B3:
	declarations:  -&gt;   scope
		w				B3
		x				B3
Block B4:
	declarations:  -&gt;   scope
		w				B4
		x				B4
Block B5:
	declarations:  -&gt;   scope
		y				B5
		z				B5
</code></pre>
<h3 id="164"><a class="header" href="#164">1.6.4</a></h3>
<p>What is printed by the following C code?</p>
<pre><code>#define a (x + 1)
int x = 2;
void b() { x = a; printf(&quot;%d\n&quot;, x); }
void c() { int x = 1; printf(&quot;%d\n&quot;, a); }
void main () { b(); c(); }
</code></pre>
<h4 id="answer-3"><a class="header" href="#answer-3">Answer</a></h4>
<p>3</p>
<p>2</p>

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